The goals of the UW CFAR Clinical Epidemiology and Health Services Research Core (CE&HSR) (formally Health Services Research Core) are to support clinical and translational HIV/AIDS research by UW CFARaffiliated investigators by providing longitudinal HIV/AIDS patient information and expertise in clinical epidemiology and health services research methods; and to foster interdisciplinary approaches to questions concerning HIV/AIDS by facilitating collaborations between clinician researchers, epidemiologists, health services researchers, biostatisticians, behavioral, and basic scientists. A main goal of the Core is to promote clinical HIV/AIDS research examining the long-term outcomes of HIV-infected patients in routine clinical practice, including the effects of antiretroviral therapy, co-morbid conditions, and complications of treatment. Additional goals of the Core are to support the conduct of interventional studies and to facilitate translational research by supplying clinical patient data linked to specimens collected on the HIV-infected population. At the start of its fifth year of the current funding cycle, the CE&HSR Core has accomplished and exceeded the goals set forth in our last application. The UWHIS has been expanded to capture new data types to support research on key HIV subpopulations. The Core maintains a registry of HIV-infected patients who are willing to participate in research studies and supports researchers preparing grant applications by identifying registry patients who meet proposed study criteria, providing lists of potential study subjects for recruitment, and addressing questions concerning clinical outcomes for persons with HIV/AIDS. The CE&HSR Core provides support to the UW HIV Specimen Repository and collaborates with the Clinical Research, Developmental, Biometrics, and Clinical Retrovirology cores to support new investigator awardees, clinical outcomes research, and translational research. Core personnel have been active in national and international cohort collaborations such as the CFAR Network of Integrated Clinical Systems (CNICS) and the North American region of the (IEDEA) project, the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD). Finally, Core resources are being used to implement technology to facilitate the collection of new patient-based measures on adherence, lipodystrophy, depression, HRQL, and substance abuse.